Dementia is an umbrella term for a range of progressive conditions that affect the brain. There are over 200 subtypes of dementia, but the five most common are: Alzheimer’s disease, vascular dementia, dementia with Lewy bodies, frontotemporal dementia and mixed dementia.
The brain is made up of nerve cells (neurones) that communicate with each other by sending messages. Dementia damages the nerve cells in the brain so messages can’t be sent from and to the brain effectively, which prevents the body from functioning normally.
Regardless of which type of dementia is diagnosed and what part of the brain is affected, each person will experience dementia in their own unique way.
Dementia can affect a person at any age but it is more commonly diagnosed in people over the age of 65 years. A person developing dementia before age 65 is said to have young onset dementia.
There are over 850,000 people living with dementia in the UK and this is set to rise to over one million by 2021.
Types of dementia
These are the most common types of dementia:
Alzheimer’s disease is the most common type of dementia in the UK. It is a physical condition caused by changes in the structure of the brain, due to a build up of ‘plaques’ and ‘tangles’, and this can result in a shortage of important chemicals that help with the transmission of messages. Alzheimer’s disease can affect concentration, decision making and everyday living skills.
Alzheimer’s symptoms tend to develop gradually over time. These may include:
difficulty remembering recent events while having a good memory for past events
issues recognising people or objects
poor organisation skills
slow, muddled or repetitive speech
reduced ability to perform everyday tasks such as cooking, bill paying, shopping etc.
problems with decision making.
Medication is available to help slow progression but it does not prevent or cure Alzheimer’s disease.
Vascular dementia is the second most common type of dementia. It is caused by problems in the supply of blood to the brain, commonly due to strokes or a series of small strokes, known as Trans Ischemic Attacks (TIAs), which cause areas of cell damage in the brain.
Changes in a person’s condition as a result of TIAs or a larger stroke are often sudden, before their condition plateaus. But the damage caused often means the person does not function quite the same way as they did before.
The signs and symptoms of vascular dementia depend on which area of the brain has been affected. Language, reading, writing and communication can be affected in vascular dementia. Memory problems may not be an issue initially, if this area of the brain has not been damaged, although they may occur later on.
Frontotemporal dementia is a progressive condition, which tends to affect younger people, usually aged 45 to 65 years, and can be difficult to diagnose. The region of the brain most affected is the frontal lobes. Frontotemporal dementia affects behaviour and personality, and this can cause disinhibition and inappropriate social behaviour. Eating patterns can also be affected, with people suddenly bingeing on food, especially sweet foods. This form of dementia can sometimes be confused with depression, stress, anxiety, psychosis or obsessive compulsive disorder.
Dementia with Lewy bodies
Dementia with Lewy bodies is a progressive condition that affects movement and motor control. A person with dementia with Lewy bodies might:
be prone to falls
have tremors (similar to Parkinson’s disease)
have trouble swallowing
shuffle when they walk
experience disrupted sleep patterns due to intense dreams/nightmares
have visual and auditory hallucinations due to the nerve cell damage.
Memory is often less affected than with other types of dementia, but a person might experience sudden bouts of confusion which can change on an hourly basis.
It is possible to have not just one but two types of dementia. The most common is a combination of Alzheimer’s disease and vascular dementia, known as mixed dementia. A person with mixed dementia would experience a mixture of the symptoms associated with the types of dementia they have.
How to get a diagnosis of dementia
If someone is showing symptoms associated with dementia it is important to visit a GP immediately. Some conditions might look like dementia, as they affect a person’s memory or brain function, but are treatable if addressed quickly. These include: infections; thyroid problems; delirium; vascular problems related to circulatory issues; vitamin B12 deficiency; sleep apnoea; stress; and depression.
To establish if dementia is present, a GP will take a medical and family history of the person, and will screen them for mental health and cognitive issues by asking questions, testing concentration, short term memory, mood and behaviour changes.
The GP may then request blood tests, an MRI or CT scan to examine the structure of the brain, or request a chest X-ray to check for any chest conditions.
They may also refer the person to a memory service/clinic, or to a specialist for further investigation and assessment.
If a diagnosis of dementia is given, the GP should then ensure that the person with the diagnosis and their family are made aware of any specialist advice and support services in their area, as well as referring them for further assessments and treatments that may help. This support can come from a range of organisations, including health and social care professionals, charities, and the voluntary sector.
Your dementia questions answered
What is young onset dementia?
Young onset dementia is when a person develops any type of dementia before the age of 65. Although the signs and symptoms of young onset dementia are similar to those seen in people over the age of 65 years, additionally there can be changes to mood, behaviour, personality and social behaviour. This can result in a delay in diagnosis as the symptoms are wrongly attributed to another condition such as: depression; stress; relationship difficulties; or work related issues.
The diagnosis is often unexpected and the loss of income (sometimes double as a partner may give up work to care for their family member) can be difficult to manage. The person’s children may be younger and also have to take on caring roles as the condition progresses.
Why does dementia affect each person so differently?
The brain is made up of two hemispheres and each has four lobes: frontal, temporal, parietal and occipital. Each lobe has a different function and, depending on which part is damaged by dementia, it can lead to different signs and symptoms. Therefore each person is affected differently.
Frontal lobes control emotional expression, personality, problem solving, judgement, motor function, language, motivation and social behaviour.
Temporal lobes control memory, speech, language comprehension, auditory and visual perception, emotional responses and facial recognition.
Parietal lobes control learnt skills such as reading, writing and calculations.
They also control recognition of objects, spatial awareness and the ability to perform complex skills such as driving and constructing things.
Occipital lobes control spatial processing, ability to determine between different colours, spatial awareness, colour and object recognition, and could also lead to difficulties with activities that require hand and eye coordination such as picking up items.
How can I avoid getting dementia?
You can’t avoid getting dementia but you can lower your risk of developing it.
Everything that keeps your heart healthy also keeps your brain healthy. So, eat a balanced healthy diet, don’t smoke, avoid drinking too much alcohol, and keep your cholesterol and blood pressure under control.
Stay physically active and mentally stimulated with different activities so that you use different parts of the brain. For example, walking, gardening, singing, art, music, reading, and all other hobbies and interests are thought to help.
There is no compelling research that says doing puzzles will improve brain health, however, learning another language is helpful because different parts of
the brain are stimulated and this can enhance cognitive function.
Is dementia hereditary?
Most cases of Alzheimer’s disease are not inherited and the majority of othedementias are not hereditary. There are some rarer causes of dementia that can be inherited, like Huntington’s disease. Although heredity does not appear to play a major part in older age forms of dementia, about 10% of people diagnosed with young onset dementia have a genetic form of dementia.
Why is the number of people living with dementia in the UK increasing?
People are more aware of dementia and it is now more widely acceptable to discuss the condition, so people are more likely to go to their GP to get a diagnosis. Also, people are living for longer and the risk of developing dementia gradually increases in people over the age of 65; over one in three people over the age of 90 years will develop dementia, and more people are living into their 90s.
Despite this, recent research has found that dementia could actually be on the decline, due to healthier lifestyle choices, such as: eating a healthy diet; stopping smoking; reducing alcohol intake; going for health screenings; exercising; taking part in social activities; maintaining good physical health.